High velocity accelerator



Sept. 2U, 1960 M. P. BROWN HIGH VELOCITY ACCELERATOR 5 Sheets-Sheet lFiled March 14, 1958 Rw, VI mWV m N0 fc wf V m@ f p a M n n n M N v...@mt B `l. J J W1 f n.. JN l M. X WMWWWMM Mm@ ma ,w u @V M w M W MF WEQ L\\\\n\ L hbwv uwN NJ mi NNW. Y\\ (uw JW WMU.HMMhflllllllllllllllllM nu.UNH HUHHW Q Il uflm: m v P @i mi q l. wv S N v\ l h\ N` b\ NN.\V u NNAI Sept.. 20, 1960 l M. P. BROWN HIGH VELOCITY ACCELERATOR 3Sheets-Sheet 2 Filed March 14, 1958 Sept. 20, 1960 M. P. BROWN HIGHVELOCITY ACCELERATOR 3 Sheets-Sheet I5 Filed March 14, 1958 R. N m 0&4 NTIL w N -JSM un TJ n.1

EHGH VELUCITY ACCELERATOR Martin ll. Brown, P.0. Box 27, Shalimar, Fla.

Filed Mar. 14, 1958, Ser. No. 721,618

9 Claims. (Cl. 89-1.7)

(Granted under Title 35, U.S. Code (1952), sec. 266) The inventiondescribed herewith may be manufactured and used by or for the UnitedStates Government for governmental purposes without payment to me of anyroyalty thereon.

This invention relates to means for increasing Ithe speed of land craftand more particularly to ltest apparatus for obtaining higher velocitiesof test vehicle on test tracks without an increase in the length of thetrack and has for an object a high speed catapult launching device forprojectiles, rockets, and other air vehicles.

At the present time it appears that the maximum velocity which has beenobtained by a test item launching vehicle on a test track is about330i() feet per second. Increase in the velocities obtainable on testtracks using present techniques is limited by the specific impulse ofavailable rocket propellants and in some cases by track length. Anobject of this -nvention is to materially increase these velocities withsuch available propellants and without increasing materially the lengthof the track.

Current practice in propelling test sled mounted test items is to employsingle or two stage boosters which are mounted on the test item sled, ora pusher sled which disengages when the booster is expended. The iuse ofadditional booster stages and increase of the track length leads to apoint of diminishing returns and for present propellants appear to be inthe vicinity of 3300 ft. per second.

Velocities of launching aircraft plus velocities of projectiles orrockets totalling 7,000 ft. per second in the future are likely, andtherefore t-he testing of ordnance at these velocities is desired, whichis an object of the .present invention.

A further object of the present invention is to employ a closed breechlauncher or tubular container into which the test vehicle track extendsand mounting the test vehicle on the track in lthe rear end of thecontainer with propelling means such as rockets and boosters facingrearwardly, the container being closed by a frangible closure at itsforward end, adapted to be displaced by the forward movement of the testsled.

A still further object includes explosive means to remove the forwardclosure when the test item approaches near the forward end of the closedbreech container.

Another object is the evacuation of the closed breech container toreduce air resistance in front of the test vehicle and test item orprojectile as it is projected forwardly through the container toward thefrangible forward closure.

A further object includes a plurality of pusher type accelerationvehicles disposed on the track behind the test vehicle for initialacceleration of the test vehicle and which disengages the vehicle whenthey are expended.

A further object is the provision of means for progressively tiring therocket means on the proceeding booster vehicles as rear boosterpropelling rockets are expended.

A further object includes means for mounting a test 2,9535 PatentedSept. 20, 1960 projectile, such as a test rocket, on the test itemsupporting vehicle so that it will be projected forwardly in space uponabrupt deceleration of the test item supporting vehicle or sled.

A further object includes the possibility of venting the closed breechor launcher tube to keep the accelerations within the container withinlimits that will not exceed the stress that can be tolerated by the testitem or sled assembly.

A further object is the provision of a gas sealing abutment meansbetween the inner wall of the breech container and the auxiliary boosterdevice disposed irnmediately in the -rear of the main rocket booster onthe test vehicle to receive the blast therefrom when the rst or rearIbooster device is expended.

A further object includes a mono-rail supporting system extending intothe breech container and forwardly thereof for the test vehicle andbooster devices to travel upon and a rear closure through which the testitem, sleds and boosters can be inserted onto the mono-rail.

A further object includes a dual rail supporting system for the testvehicle and booster devices in which the tracks or rails are disposedoutside of the breech loading container, and the container is slottedlongitudinally at its top, with means supporti-ng a test vehicle on therails outside and means extending through the slots connecting the testvehicle and booster device for travel on the rails.

Other -objects and advantages will become apparent from the followingdescription and accompanying drawings in which like reference charactersrefer to like parts in the several figures of the drawing.

Figure 1 is a somewhat diagrammatic vertical longitudinal sectional viewthrough a test vehicle launcher, parts being broken away to foreshortenthe view.

Figure 2 is a transverse vertical section taken about on line 2 2 ofFigure vl.

Figure 3 is a diagrammatic vertical longitudinal sectional view, on asmaller scale showing the test vehicle within the closed breechreceptacle being projected forwardly by the tirst booster device, butbefore reaching the forward frangible seal, and showing the means forexhausting air from the interior of the closed breech container.

Figure 4 is a fragmentary diagrammatic sectional view of the deviceillustrating how the second or main booster takes over when the rstbooster 4becomes expended.

Figure 5 is a further diagrammatic view illustrating the test vehicle atthe end of its travel, where it leaves the end of the track or rail andstrikes the deflector, with the test item, or projectile projectedforwardly at maximum velocity.

Figure 6 is a slightly modified longitudinal vertical sectional viewsimilar to Figure l in which more than one booster device is employedwithin the closed breech container.

Figure 7 is a view similar to Figure 3, but showing how the secondbooster can be fired while the rear or iirst booster is still i-noperation to further increase the velocity of the launching sled whileit is within the closed breech launching tube.

Figure 8 is a further modification of the invention in which thelaunching device is supported on dual parallel guide rails located aboveand at opposite side of the launching tube, and in which the tube isslit longitudinally with means extending through the slit for connectingthe booster devices to their slippers on the rails. In this form twobooster rockets are disposed to function within the tube and the mainbooster rocket on the test vehicle is disposed to operate outside of thelaunching tube.

Figure 9 is a transverse vertical section taken about line 9 9 of Figure8.

Referring rst to Figures `1 to 5 the reference numeral 1 denotes aprepared rigid support or base, such as the ground or a cementfoundation on which my device is mounted. t

A closed breech container or launching tube 2v preferably of cylindricalform -i-s rmly supported on the base 1 and a mono-rail 3, preferably ofT shape is suitably secured at the bottom of the tube -2 to its innerperiphery. The track or rail 3 terminates at its rear end at 4 adjacentthe breech end of the launching tube 2, this end of the tube beingflanged at 5 with a removable breech closure or plate 6 secured over theloading endy of the Itube by suitable securing means, such as bolts 7.If desired any suitable quick, removable breech sealing closure can beemployed.

The rail 3 extends forward materially beyond the mouth 8 of thelaunching tube 2 yand is rigidly supported by suitable supports yorbrackets from the base 1 to maintain the track in a precise straightline.

In practice the closed breech launching tube or cylinder 2 may inclose aconsiderable portion of the track. In a 3000 foot track the ylaunchingtube may incluse '1000. or more feet Vof track, if desired.

A frangible closure or cap 9 is provided to seal the mouth 8 of thecontainer or tube 2. If desired an explosive 10 may be associated withthe frangible vcap' 9 for the purpose of disintegrating or removing thecap just prior to the test vehicle or sled 11 reaching the cap.

The test item supporting vehicle is indicated generally at 11 andcomprises a guide shoe forming a slipper base 12 as shown in Figures 1and 2 to fit and slide on the guide rail 3.V The test vehicle is formedwith a test item support 13 upstanding therefrom to receive and supporta test item 14 such as a rocket, projectile shell or other aerodynamicitem in spaced parallel relation to the guide rail 3. Suitable brackets15 being provided on the support 13 for receiving and holding the testitem 14, with release means for preventing rearward movement of the testitem relative to the test itemsupporting 'vehicle 11 but permitting thetest item 14 to continue forwardly at maximum velocity when the testvehicle is decelerated, such as shown in Figure 5, by a stop means ordeector 26 in the path of the test vehicle 11.

Firmly secured to the test vehicle 11 in rear ofthe support 13 is themain test vehicle accelerating device such as a booster rocket orrockets 16 which are supported from the slipper base 12 of the testvehicle 11, by spaced supports 17.

Mounted on the rail 3 in rear of the guide support or slipper base 12ofthe test vehicle 11 is a primary or first booster vehicle 18comprising Va slipper base or iirst booster `sled 19 designed toyslidably fit the rail 3; The sled 19 :has upstanding standards orbrackets 20 firmly fixed thereto into which is rm'ly fixed a primary orfirst booser device ysuch as a booster rocket 21.

Mounted at the forward end of the pri-mary booster rock-et 21 is anabutment disk in the form of a gas seal 22, the periphery of which isshaped to` conform to the inner shape of the breech launching containeror cylinder 2, but in fairly closely spaced relation to the interior lofthe container tube 2 so as to travel therein,V preferably Withouttouching.

Suitable tiring mechanismsuch as electric conductors 23 may be connectedto the igniter of the booster rocket 21 from the exterior of thecontainer`2. Also suitable tir-ing means may be provided `such asconductors 24 for tiring the main or primary booster rocket 16 when thefirst booster rocket 21 is Wholly or partly expended when separation ofthe rst booster device'ignites the main booster rocket 21. Also suitablecontacts and conductors 25 may be provided for energization bythe testitem sled 12 las the same approaches the frangible closure i cap or seal9 to fire the explosive 10 to remove or disintegrate the closure cap 9slightly before the test item sled 12 reaches the cap 9.

It is also contemplated that the cap 9 may be made rof lhighly frangiblematerial so that the striking of the cap '9 by the test item 14 maydisintegrate or remove the cap 9 to one side to permit the test item 14and sled 12 to pass out of the tube 2 without material deceleration ordama-ge. Y

-In |loading the device for a test the closure cover 6 is removed byremoving the bolts 7, although other quick release lsecuring means. forthis breech plate 6 may be t provided.

Y per 12 maybe introduced ifdesired.F

The test item supporting sled 11 is now inserted through the breech ofthe container or cylinder 2 with the slipper base y12 slidably disposedon the rail 3 as shown. Suitable lubricants between the rail 3 and slip-The firing Iconductors 24 :are now connected yto asuitable, firingmechanism which preferably is carried on forward surface of the gas seal22. The gas seal 22 and its associate booster sled 1S are now insertedthrough 26 located in the forward or muzzle portion 8 of the tube 2 forevacuatingl the air from within the tube.

Before tiring the rocket '21 the air within the tube 2 is preferablyevacuated through the conduit 26 connected to suitable vacuum pump means26a to provide a partial vacuum within the tube 2, ythis beingmaintained by the sealing closure 6 at the breech end and the frangib'leclosure cap V9 at the forward or muzzle end 8.

Y With the booster sled 11 `and auxiliary booster sled 18 in theposition approximately as sho-wn in Figure l the auxiliary or rstbooster rocket 21 is fired in any convention'al way, such as energizingthe conductors 23 to re a ysquibyin the rocket 21 Vto ignite the rocketproper.

The rocket 21 accelerates the auxiliary sled 19 for-y wardly, Vwhich inturn pushes the test vehicle sled 11 forwardly as shown in lFigure 3.The gas seal or shield 22 prevent an appreciable amountV of pressuregenerated by t'he rocket 21 behind the shield 22 from leaking for`wardly while the flow pressure area in the tube 2 ahead ofthe shield 22assisted in increasing the acceleration and velocity of the test itemsled 11 and the test item 14 carried thereby.

At `some point duringits forward travel, either Within the container 2or after it has passed out of the container 2 the primary or mainrocketv booster 16 is fired, preferably as the propellant forceof'theauxiliary booster 21 falls off or becomes expended.

Y The blast of the primary rocket booster 1e strikesthe gas shield' 22,decelerating the first booster 1S with a corresponding further increasein acceleration and velocity of the test `vehicle sled 11. Y A When thetest item supporting vehicle sled 11 ap-A proaches the frangible muzzlesealing cap 9` the contacts 25 are closed, preferably, bythe testvehicle sled 11,` tol re" the explosive 10 to remove or disintegrate thecap 9 so thatit lwill not damage or'decelerate the test vehicle Y sled11 or injure the test item 14.

, the way without vany appreciable' loss inV acceleration of the testitem sled 11 in the event that the explosive '1u is not employed. It isalso contemplated that beforetbe time when the test vehicle 11 reachescap 9 the vacuum in the tube 2 will be decreased to provide a positivepressure ahead of the seal 22, which is sutcient to pop the closure cap9 to one side out of the way of the test vehicle 11 and test item 14.

The main booster, or boosters 16 on the sled 11 continue to increase thevelocity of the test vehicle 11 and test item 14 until the sled 12 nearsor reaches the far end of the rail 3 as shown in Figures 4 and 5 wherethe test vehicle and test item have reached the maximum velocitypossible for the system, length of track and amount of booster powerprovided.

The primary booster rocket 16 on the sled 12 preferably becomes expendedas it leaves the far end of the rail 3, as shown in Figure and the testVehicle is preferably quickly decelerated by a suitable deflector o-ryieldable abutment 27 but the test item 14 Vis projectedV freelylforwardly as shown, at the maximum velocity of the test item sled 11.It should be obvious that with the closed breech container or tube 2 andthe removal of air from the interior of the tube 2 by suction throughconduit 26 to reduce air resistance within the tube to a minimum, a verygreat increase in acceleration and velocity can be obtained without amaterial increase in the length of track required or in the propulsiveforce of the booster rockets that are employed.

The modification as shown in Figures 6 and 7 primarily involves the useof a plurality of secondary booster sleds each having a gas shield orseal similar to 22. In this form the main test item and sled areassigned similar reference numbers to those used in the preferredembodiment, as they are of the same type as in Figures l to 5. Aplurality of booster sleds are indicated at 18a and 18b each havingslipper supports or bases 19a and 19b and gas seal shields or partitions222L and 22b carried on the front ends of the booster rockets 21a and2lb which are supported on brackets 20a and 261. Any suitable firingmeans, for instance a timer device may be provided to fire boosterrockets 20a and 20h successively in their desired tiring order and time,preferably the rear booster rocket 21a is iired iirst and as it becomesexpended any suitable mechanism fires the intermediate stage booster2lb, causing separation between the two booster stages, as seen inFigure 7. As the intermediate stage booster rocket 21b becomes expendedthe main booster rocket 16 on the test item support 11 is tiredincreasing the acceleration and velocity of the test item 14 to agreater degree than when a single auxiliary booster is employed. Theoperation and rocket tiring means may otherwise be 4the same asdescribed in connection with Figures l to 5.

Referring to modiiication shown in Figures 8 and 9 the closed breechcontainer is indicated generally at 2S, anged at its rear or breech end29 to receive a breech closure plate or seal 30 which is removablysecured thereon by any suitable quick removable securing means such asbolts 31.

The tubular container or elongated cylinder 28 is slit longitudinally toprovide a narrow guide slot 32. The container or launcher tube 28 isalso preferably held from spreading under internal pressure by retainingmeans 33 which in cross section almost surrounds the tube 28 leaving theslot 32 exposed.

The breech launching container 28 is, of course, rigidly supported on asuitably prepared base 34 which extends upwardly on opposite sides ofthe container 28 as indicated at 3S to support a pair of spaced rails 36forming the track on which test items supporting vehicle 37 and theprimary and intermediate booster devices 38 and 39 are slidablysupported on slipper members or supports 40 which slidably engage andpartly inclose the rails 36.

In this form the test item vehicle 37 is supported from its slippermembers 40 by a transverse support or base plate 41:L between theslippers on which the test item support 41 -is rigidly carried. Thesupport 41 carries 6 longitudinally spaced brackets 42, similar to themerribers 15 in Figures l to 5, in which the test item 43 is detachablycarried for forward projection as in the preferred form of the inventionand is releasable for free forward ight when the support 41 ismaterially decelerated after forward acceleration.

Mounted on the transverse support 41a immediately behind the test itemsupport 41 is the main or No. 3 booster rocket 44 (or rockets if morethan one is used and are placed side by side).

The booster rocket 44 is rigidly mounted on brackets 45 carried on thetransverse supporting plate 41a just referred to.

In order to provide for maximum acceleration of the test item supportingvehicle a plurality of auxiliary boosters 38 and 39 are provided. Theseboosters each have a Vtransverse supporting plate 41ar and slipperchannels 46-47, preferably C shape in cross section to slidably iit thespaced T rails 36. Projecting downwardly from the center of each of theplates 41a is a comparatively thin longitudinally disposed iin orsupporting plate 48. The plate or iin 48 is disposed to guidingly t theslot 32. As seen in Figure 9 the lower end of the ns or plates 48 areeach formed to provide a booster rocket holder or body 49 for rigidlysupporting one of the iirst of intermediate booster rockets 50 inconcentric relation to the central axis of the launcher tube 28.

Gas seals in the form of circular abutment partitions 51 and 52 arefixed to the rocket holder or body 49 at the rear and front ends of thebody 49 to closely conform to the interior of the test vehicle launchertube 28, in spaced relation to the inner periphery to provide a gas orpressure seal in a similer manner to the abutment partitions or disks 22in the preferred forms shown in Figures 1 to 7.

The tinack or rails 36, of course, extend forward materially beyond themouth of the launcher tube or cylinder 28 and a closure cap (not shown)of a frangible nature similar to the cap 9 and cap disintegrating orremoving means such as an explosive (10 as Aseen in Figure l) may lbeprovided if desired, also any suitable displaceable seal may be providedto close the slot 32 before and after the ns 48 of the booster devicespass along the slot. This sealing means, not shown, may be in the formof a resilient sealing strip carried by one or both longitudinal edgesof the -tube 28 which define the slot 32, movement of the ns 48displacing the sealing means progressively from end -to end las theboosters 3S are yaccelerated forwardly by the rockets 50, the resilientmeans, or springs may be provided for, returning the sealing stripsacross the slot 32 in sealing rela-tion as the ns 48 pass along the slit22.

The tracks are maintained in straight longitudinal alignment andparallel relation beyond the outer end of the breech loading tes-t itemlaunching tube 28, and as in the preferred `form shown in Figure 5 ayieldable abutment or deector such as 27 is placed beyond the forwardend of the track to arrest movement of the test item supporting sled 37,as it leaves the end of the track so as to decelerate the sled and causethe test item 43 to be projected forwardly in space at the maximumvelocity of the sled 37.

With .the construction shown in this modification it is also possible toload the device through the rear or breech 30 of the launching tube 28as in the preferred embodiment since the rails 36-36 are displacedlaterally out of alignment with the ilange 29 and seal plate 30. It isnecessary however that the ange 29 be slotted to receive the fins 48,also that the supporting base plates 41a, of the boosters 38 and thebase plate 411L of the test vehicle 37 be elevated sutiiciently at thecenter to clear the upper periphery of the ange 29.

After the breech `closure plate 30 is removed the runners or slippers 40of the supporting sled 37 are irst slipped onto the rails 36 |and pushedforward as shown in Figure 8, the tt item 327 of cou-ree, beingpositioned in the brackets 42, and the rocket booster 44 placed inposition in the braokets 4 5. v

'-.helinterrnediate acceleration booster 49; is now slipped through thebreech of the launching tube 28v Iwith. the slippers 47 slidablyengaging the rails 36 and is moved forwardly into contact with theslippers 40 of the test item supporting vehicle 37. This disposes thesealing partitions 1---5if in closely spaced relation tothe innerperiphery of the launchingA tube 28, as. shown, one gasv s ealat eachend of the rocket booster holder or body 49, providing a double gasseal. Y Y

` The iirst or initial auxiliary booster 38 is now inserted.

in the breechof the` launchingV tube with its lslippers 47 engaging thetrack 36 and the intermediate booster slippers 47. in a similar mannerwith the depending iins 48V in the guide slot 3,2.

It is to be understood that suitable means are provided for 4initiallyfiring the first booster rocket 50, and subsef quently tiring theintermediate booster rocket S0` inthe desired time sequence, preferablyas the forward thrust of the first booster stage diminishes. Likewise,in a similar manner the main `booster rocket 43 is fired'. In this formof the invention it might be desirableto -ire the main test item sledrocket 44. while the intermediate booster rocket is functioning. Alsoany suitable tiring means may be used such as shown in the. preferredform, where during inal acceleration of the first booster, suitablecontacts rire the intermediate booster rocket, which in turnsubsequently fires the main booster on the test item sled. It should benoted that a preset timing device m-ay be used and carried by the sled37 to iire the two booster` rockets v49 and main booster rocket 44 inthe desired order and time sequence.

It will be obvious that various changes may be made by 4those skilled inthe art in the details of the embodiments illustratedin the drawings anddescribed in detail within the principle and scope of the invention asexpressed in the appended claims.

I claim:

l. A closed breech test item` launching device comprising an elongatedlaunching4 tube having a closed breechl end, a test item supportingYvehicle, a track` extending in parallel relation to said tube from apoint adjacent the breech end ofsaid tube toa point materially beyondthe forward end orf saidtube, said vehicle having slippers. disposed onsaid track `for sliding engagement therewithl from end to end, test itemsupporting means rigidly iixed on said vehicle abovethe level ofsaidtrack to support a test item thereon, a booster rocket fixed on saidtest vehicle rearwardly of said test item supporting means for,

means iixed on said bodyin parallel relation to the axis of said tubeincludingra rocket fixed on said body `facing saidbreech end, la gassealing partition carried bysaid auxiliary booster deviceA defining theinterior of said launching tube in closely spaced relation, to retardthev p-assageY-of pressure gases from` said auxiliary boosterrocketrpast said partition, removable closure means for` the breech endof said tube, and means for tiring saidy auxiliary booster rocketwhilethe same is in said tube.

2. Apparatus as clraimedin claim l including a frangible.

sealingl closurecfor the forward end of said tube, and means forexhausting air` from the interior of said tube.

3. Apparatus as set forth inclaim, 2 in which the air exhausting meansis.l located adjacent the yforwardwend `of the tube. v y

. 4..,A closed breech,launchingYdevice` comprisingnan Y elongatedsupporting base, ahtest vehicle` acceleratimvtrkfatalities-Srbsfantially the'.lensthoffsaidf-base- .an

elongated closed breech test vehicle launching tube havinga central axisdisposed in spaced parallel relation to said track throughout a materialportion thereof,V a test item2 supporting vehicle havingY elongatedslipper means slidAi ably engaging said track for acceleration thereonfron-r end to end, of the track, a test itemx support ixed on saidslipper means above the level of said track, means for mounting atestitem on said test item support in spaced parallel; relation to Isaidtrack for free flightV forward uponrabrupt deceleration of said vehicle,booster rocket means fixed on said slipper means rearwardly of said'test item support for discharge rearwardly, a plurality ofauxiliarybooster rocket devices each having slipper means slidablyengaging said track rearwardly of said test iterrr supporting vehicleslipper meansv for pushing engagement therewith, said `auxiliary boostermeans each having a, body portiondisposedto travelwithin said launchingtubein spaced relation to the inner periphery of said tube, an;auxiliary booster rocket fixed` on said body portion having;

a discharge nozzle facing the breech closure means of said? tube,` a gasseal disk xedon said auxiliary booster device in front of the forwardend of said auxiliary booster; rocket device,A said disk deiining theinner periphery ofsaid tube in closely spaced relation thereto, afrangible.v closure forv the frontend ofsaid tube forsealing thesameagainst the entrance of outside air, and means for exhaustingtheairl from withinsaid tube adjacent the mouth thereof to provide apartialvacuum in said tube betweenI said ygas seal disk and said frangibleclosure when one of said auxiliary booster rockets is tired.

5. A closed breech test item acceleration and launching` devicecomprising an elongated test item launching cylinv der having a breechend for receiving said test item therethrough, removable closure meansfor closing and sealing,

said breech end, a highly frangible closure cap for closing and sealingthe muzzle end of said cylinder, a test item vehicle supporting vehiclerail having a rear end disposed `adjacent said closure means inforwardly spaced relation thereto, said rail disposed in iixed parallelrelation to said:

cylinder and terminating in a forward end disposed materially forward ofsaid muzzle constituting an acceler-` ation track, a test itemsupporting vehicle comprising, elongated slipper means slidably engagingsaid rail, means` for Ireleasably supporting an elongated test item'onsaid slipper means above said rail, main booster rocket, means forfixing said booster rocket iny said cylinder on saidl slipper means inrearwardly spaced relation to said testv item and parallel to said rail-with itsdischarge end facing rearwardly toward said closure means, anauxiliary rocket booster device comprising an elongated supportingslipper `member slidably enga-ging said rail rearwardly of said' testvehicle slipper means, an auxiliary booster rocket` iixedly carried bysaid slipper member within said launching cylinder having a dischargeend facing rearwardly toward said removable closure means, a lgassealingV disk fixed on said auxiliary booster device in front of saidauxiliary booster rocket, said disk having a periphery deiiningy theinterior of said launching cylinder in closely` spa-ced relationthereto, Iand means for tiring said auxiliary booster device while thes-ame is in said cylinder.

6. A high accelerationV test item propelling apparatus comprising anelongated cylinder, having a breech endl and a muzzle end, a removableclosure for sealing said breech end, a frangible closure cap for sealingsaid muzzle end, means connected to said cylinder for exhausting airfrom the interior of said cylinder, a straight elongated test vehiclesupporting rail extending from a point adjacent said removable closureto a point materially beyondv said muzzle end in spaced parallelrelation to the axis of said cylinder for a test item supporting vehicleto travel thereon, a test item supporting vehicle carried on said rail,main -boosterrocket means fixed thereon within saidV cylinder with itsdischargeend facing in a Adirection to-.- ward said removableclosure, anauxiliary booster device. disposed lon .saidrail rearwardlyI of saidtest item sup` porting vehicle for accelerating said test itemsupporting vehicle forwardly on said rail, auxiliary booster rocketmeans fixed on said auxiliary booster device within said cylinder withits discharge end facing said closure means, and la gas ysealing diskcarried on said auxiliary booster device within said cylinder having aperiphery closely detining the inner periphery of said cylinder inspaced relation thereto perpendicular to the axis of said cylinder, saiddisk having a front surface facing the disch-arge end of said mainbooster rocket means, and means for tiring said yauxiliary boosterrocket means and said main booster rocket means successively.

7. Apparatus as set lforth in claim 6 including means for removing saidfrangible closure cap out of the path of said `auxiliary -booster rocketmeans at a predetermined point during its travel toward said frangibleclosure cap.

8. A high acceleration device for test items comprising an elongatedtest item receiving cylinder having a breech end and la muzzle end, anelongated test vehicle supporting rail extending within said cylinder atthe bottom thereof from a point adjacent said breech and to a pointmaterially beyond the muzzle end for a test item supporting vehicle totravel thereon, a test item supporting vehicle disposed within saidcylinder on said rail adjacent said breech end, a removable breechclosure for inserting said vehicle through said breech end onto saidrail, means on said vehicle for supporting a test item within saidcylinder, rocket acceleration means carried by said test vehicle withinsaid cylinder having its discharge end facing toward said breechclosure, a frangible closure cap for sealing the muzzle end of saidcylinder against the entrance of outside lair into the cylinder, meansconnected to the cylinder adjacent the muzzle end thereof for exhaustingthe air from within said cylinder to provide a partial vacuum within thecylinder, means for tiring said rocket accelerating means within saidcylinder, and means for removing said closure cap from said muzzle endduring the acceleration of said test vehicle by said rocket accelerationmeans toward said frangible closure cap, said closure cap removing meanscomprising an explosive for removing said closure cap, and meansactivated by said test item supporting Vehicle for exploding saidexplosive prior to said test item supporting vehicle reaching saidclosure cap to remove said closure cap from said muzzle prior to saidtest item supporting vehicle or said test item reaching Said closure capduring forward movement of said test item supporting vehicle in saidcylinder, -an acceleration booster device disposed within said cylinderon said rail between the test vehicle and said breech closure forpushing said test vehicle tward said frangible closure cap, said boosterdevice having a rocket motor xed thereon facing said breech closure, agas sealing partition disk carried on said auxiliary booster deviceperpendicular to the axis of said cylinder with its periphery closelydefining the inner periphery of said cylinder in closely spaced relationthereto, said gas sealing partition disk being positioned on saidauxiliary booster device intermediate the auxiliary booster devicerocket motor and the rocket acceleration means of the test itemsupporting vehicle with a front surface facing the discharge end of therocket acceleration means for the test vehicle, and means for firingsaid auxiliary booster rocket motor within said cylinder while adjacentsaid breech end, and means for subsequently tiring said rocketacceleration means on said test vehicle.

9. A high acceleration device for test items comprising an elongatedtest item receiving cylinder having a breech end and a muzzle end, anelongated test vehicle supporting rail extending within said cylinder atthe bottom thereof from a pointadjacent said breech end-to a pointmaterially beyond the muzzle end for a test item supporting vehicle totravel thereon, a test item supporting vehicle disposed within saidcylinder on said rail adjacent said breech end, a removable breechclosure for inserting said vehicle through said breech end onto saidrail, means on said vehicle for supporting a test item within saidcylinder having its discharge end facing toward said breech closure, arangible closure cap sealing the muzzle end of said cylinder against theentrance of outside air into the cylinder, means connected to thecylinder adjacent the muzzle end thereof for exhausting the air fromwithin said cylinder 4to provide a partial vacuum within the cylinder,means for firing said rocket accelerating means within said cylinder,and means for removing said closure cap from said muzzle end during theacceleration of said test vehicle by said rocket acceleration meanstoward said closure cap, in which said closure cap removing meanscomprises an explosive for removing said closure cap, and meansactivated by said test item supporting vehicle for exploding saidexplosive prior to said test item suporting vehicle reaching saidclosure cap, to remove said closure cap from said muzzle prior to saidtest item supporting vehicle or said test item reaching said closure capduring forward movement of said test item supporting vehicle in saidcylinder.

References Cited in the le of this patent UNITED STATES PATENTS1,416,828 lHolmes May 23, 1922 2,385,051 Berlin et a1. Sept. 18, 19452,485,601 Hickman Oct. 25, 1949 2,734,702 Northrop et al. lFeb. 14, 19562,792,754 Walker May 21, 1957 2,792,755 Lahde May 21, 1957 2,817,272Gunder Dec. 24, 1957 2,870,675 Salisbury Ian. 27, 1950

